Research On Key Technologies Of FBMC System

With the continuous evolution of the communication industry,wireless communication technology has developed rapidly, people's requirements for communication technology have become increasingly high. Nowadays, the fourth (4G) generation. mobile communication system has been used largely. In the 4G mobile communication system,Orthogonal Frequency Division Multiplexing(OFDM) technology is the main multi-carrier modulation technology of the physical layer. But in the application situations of Cognitive Radio and Tactile Internet, the OFDM technology of the 4G communication system has exposed obvious shortcomings, such as adding the cyclic prefix to the OFDM system to reduce the spectral efficiency, pulse shaping used the rectangular pulse to add the out-of-band radiation. These shortcomings make OFDM tecnnology no longer be the most competitive air interface waveform technology in the next generation mobile communication network. In order to overcome the shortcomings above, non-orthogonal multi-carrier technology represented by FBMC is expected to be used in the 5G mobile communication system. So the FBMC technology becomes the content of this paper.The main content of this paper is the key technology research of FBMC system. Firstly, the basic principle of FBMC system is introduced,and the system model of FBMC is studied, including the concrete design and implementation method of the transmitting link and the receiving link.Secondly, in the aspect of receiving detection algorithm, this paper applies the LMS algorithm based on time-domain equalization to the FBMC system. Through comparing with the detection performance of the LMS algorithm in OFDM system, this paper studies the performance of LMS algorithm used in FBMC system. Then, in the aspect of the channel estimation of the FBMC system, this paper studies the effective and reliable channel estimation algorithm which can be applied to FBMC system. The traditional LS algorithm has the disadvantage of poor performance. And though the performance of MMSE algorithm is better but the implementation complexity is very high. Therefore, on the base of making sure the performance of channel estimation, in order to solve the problem of reducing implementation complexity and improving spectrum efficiency, Compressed Sensing theory is applied to the channel estimation of FBMC system, and it achieves better performance.Finally, through performance simulation, it is proved that the LMS algorithm can be applied to the receiving detection of FBMC system. And it is feasible and effective to apply the channel estimation algorithm based on the Compressed Sensing theory to the channel estimation of FBMC system.